An integrated circuit (IC) is a miniaturized electronic circuit including semiconductor devices and passive components and which is manufactured in and on the surface of a thin substrate of semiconductor material. Integrated circuits are used for a variety of devices and a multitude of applications due to their low cost and high performance.
A high number of integrated circuits are fabricated simultaneously on a semiconductor substrate. Once the integrated circuits are completed, the semiconductor substrate is sawed into individual chips. Conventionally, the uppermost surfaces of the chips are generally protected by a passivation layer disposed over the integrated circuit. This passivation layer, however, cannot cover the periphery of each chip. Thus, the periphery of each chip is exposed to undesirable moisture and ionic contaminants. Accordingly, metal seal rings are commonly formed around at least the upper periphery of the chip as part of the integrated circuit fabrication process, prior to sawing the substrate. Seal rings are formed of one or multiple metal layers and can provide structural reinforcement and stop undesirable moisture and mobile ionic contaminants from entering chip active circuitry regions and affecting operational reliability.
Decoupling capacitors are also necessary components of integrated circuits. Decoupling capacitors decouple portions of the IC from one another. Noise created by circuit elements is shorted by the decoupling capacitors which are critical for power/ground connection integrity and necessary for achieving high performance and reliable circuit operation. In advanced semiconductor processing operations, the energy consumed per unit area of an integrated circuit device is increasing and the IR drop is worsening due to lessened metal thicknesses, thereby degrading the overall power and ground stability. Accordingly, an increasingly high number of decoupling capacitors is needed. Each decoupling capacitor requires a considerable amount of device area which generally comes at the expense of other device features, however. It would therefore be desirable to provide decoupling capacitors that do not create the above shortcomings on integrated circuit chips.